The last scientific achievement of Etienne Jules Marey,(1830-1904), was his Institute, which was devoted to the standardization and checking of physiological instruments. During his life, he pursued the aim of making physiology" an exact science". The geometric representation of movement and the standardization of devices describing it, were the methods by which he intended to achieve this aim. However, Marey established his Institute at the end of his life, without securing its continuity. This article describes the history of this scientific institution and includes some previously unpublished documents. It emphasizes the turning-points which characterized its brief existence and concludes with a reflection on Marey's heritage.